Japanese Patent Laying-Open No. 4-88837 (Patent Literature 1) discloses a charge controller controlling battery charging. In this charge controller, full charge is detected by detecting a voltage drop (−ΔV) after full charge, and detection accuracy of −ΔV is varied in accordance with ratings of a battery to be charged, and the like. Accordingly, suitable charging can be performed depending on the type of battery (see Patent Literature 1).